The Unite union said it would hold a “consultative ballot” for action unless what they said were a number of issues were addressed,

Unite regional officer Tony Trench said its members at Lothian Buses were at “breaking point” and threatened a strike which would cause widespread disruption and a “stoppage of the service” affecting 1700 drivers.

In turn, the company said it was “shocked and deeply disappointed” that the union had not tried to resolve its concerns directly.

The union cited what it said were safety issues and even alleged Unite members were “banned from meetings”.

In a statement, Mr Trench said: “The intimidation of union members by Lothian Buses management is a disgraceful development.

“Unite members are being banned from attending meetings relating to the operations of the buses in clear breach of our collective agreements.”

The Union also claimed the provision of gloves for drivers using manual ramps for wheelchairs instead of mechanical ramps was withdrawn by management.

“The actions to remove the safety glove provision are beyond belief, and worse than that it’s dangerous,” added Mr Trench. “Unless these hostile decisions are reversed, Unite will have no option but to launch a consultative ballot for industrial action.

“Our membership love the buses, we love the public and we love to provide a solid standard of service but we are running at nearly 100 drivers short because of a problem of retention – all to do with the current culture.

“I am sure the public of Edinburgh will be utterly dismayed by the actions of Lothian Buses management who are prepared to risk widespread disruption due to a failure to include the workforce in meetings and to ensure the safety of drivers at little cost.”

A Lothian Buses spokesman hit back at the claims and said there had been little effort to resolve the issues on the part of the union.

“We are shocked and deeply disappointed that Unite have not tried to resolve any concerns with us directly.

“Any industrial action would only bring significant inconvenience to our many customers who rely on our services every day and is not in the best interests of Unite’s members and our other staff in the longer term.

“Our commercial success in recent years has allowed us to create new jobs and provide a 6 percent pay increase over three years from 2016.

“We would strongly encourage Unite to follow the agreed due process for resolving disputes.”

The council, which is the majority shareholder in Lothian Buses said it had been made aware of the situation and the potential for industrial action by Unite members. It urged a “speedy resolution”.

A council spokesperson said: “Our priority is to ensure the city keeps moving, particularly during this busy time of the year, and for Lothian Buses customers to enjoy the best possible service.